001/**
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018
019package org.apache.hadoop.mapreduce.lib.map;
020
021import java.io.IOException;
022import java.util.StringTokenizer;
023
024import org.apache.hadoop.classification.InterfaceAudience;
025import org.apache.hadoop.classification.InterfaceStability;
026import org.apache.hadoop.io.IntWritable;
027import org.apache.hadoop.io.Text;
028import org.apache.hadoop.mapreduce.Mapper;
029
030/**
031 * Tokenize the input values and emit each word with a count of 1.
032 */
033@InterfaceAudience.Public
034@InterfaceStability.Stable
035public class TokenCounterMapper extends Mapper<Object, Text, Text, IntWritable>{
036    
037  private final static IntWritable one = new IntWritable(1);
038  private Text word = new Text();
039  
040  @Override
041  public void map(Object key, Text value, Context context
042                  ) throws IOException, InterruptedException {
043    StringTokenizer itr = new StringTokenizer(value.toString());
044    while (itr.hasMoreTokens()) {
045      word.set(itr.nextToken());
046      context.write(word, one);
047    }
048  }
049}